During resent years, internal combustion engines for, for example, vehicles have been designed towards an improved operational economy and a reduced effect on the environment by means of introduction of digital control systems for optimization in different operation situations. This is, for example, the case for fuel injection, ignition, variable compression and controllable valves. As to the methods for transforming the heat that is lost via cylinder cooling and exhaust gases into work, there has not been any remarkable improvement.
Different variants of water injection into internal combustion engines have been tested. On one hand, the intention has been to decrease the combustion temperature in order to reduce the generation of nitrogen oxides, on the other hand the intention has been to decrease the cooling losses in order to obtain a high degree of executed work. Furthermore, there have been attempts to inject high pressure water steam in connection to the combustion. The high pressure steam has been generated by evaporation of water by means of hot exhaust gases. The attempts have shown that the generation of nitrogen oxides decreases upon use of water/water steam. Furthermore, an improved efficiency has been proven. A problem that has restricted said attempts is that, during injection of water/water steam, large amount of energy is consumed, as the injection takes place in connection to the end of a compression stroke and/or during combustion, when the cylinder pressure is high. Another problem with a restricting effect is that the presence of a substantial amount of water, with an important cooling effect during the evaporation, has effected the combustion, resulting in an unwanted increased of non-combusted hydrocarbons. The positive effects has not compensated for said drawbacks.
The present invention eliminates said problems, and heat that is normally lost via cylinder cooling and via exhaust gases is, to a remarkable degree, transformed into work.